Brazilian version of the CHOP INTEND scale: cross-cultural adaptation and validation

Background  Spinal muscular atrophy (SMA) is a rare genetic disease that causes progressive muscle weakness and impacts motor function. The type I is the most severe presentation and affects infants before 6 months old. In addition, the instruments available for assessing motor function have limitations when applied to infants with neuromuscular diseases and significant muscle weakness. Objective  To translate, cross-culturally adapt, and validate the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) to Brazilian Portuguese. Methods  The present study comprised the translation, synthesis of translations, backtranslation, consolidation by a committee of experts, and test of the final version of the CHOP INTEND in 13 patients with SMA type I. We also assessed the content validity and reliability of the translated version. Results  The scale was translated considering semantic, structural, idiomatic, and cultural aspects. All agreement rates were > 0.8, the overall content validity index of the instrument was 0.98, and inter-rater reliability using the intraclass correlation coefficient was 0.998. Conclusion  The Brazilian version of the CHOP INTEND met semantic and technical equivalence criteria with the original version and was valid and reliable for patients with SMA type I.


INTRODUCTION
][7] Spinal muscular atrophy is a rare genetic disease that affects the motor neurons, causing hypotonia, progressive muscle weakness, and delay and loss of motor function. 8,9The disease is classified according to age of onset of symptoms and maximum motor function achieved, which results in a wide spectrum of phenotypes grouped into four types (I, II, III, and IV). 1,8,9bout 70% of SMA cases are classified as the most severe type (I), characterized by early symptom onset (that is, before 6 months of age), difficulty in cervical control, and inability to sit and roll over. 8,10Over time, the loss of motor function results in reduced movements and intolerance to some postures. 3,8In addition, the progression of the disease leads to respiratory impairments, paradoxical breathing, chest restriction, bell-shaped chest, hypoventilation, and respiratory failure. 9,11,124][15] The scale presents good sensitivity, reliability, and responsiveness over time and may be an ideal instrument for assessing infants with SMA type I who cannot sit. 13,14he CHOP INTEND was based on the Test of Infant Motor Performance with the addition of new created items to analyze the spontaneous activity, directed movements, and reflexes of patients.][15][16] The Hammersmith Infant Neurological Examination and Motor Function Measure are two instruments translated into Brazilian Portuguese and applied to patients with neuromuscular diseases.However, these instruments may not present adequate sensitivity to patients with SMA type I with limited movements and unable to sit. 17,18hus, our study aimed to translate and cross-culturally adapt the CHOP INTEND scale into Brazilian Portuguese and assess its content validity and reliability.

METHODS
0][21] The study was approved by the research ethics committee of the Instituto de Medicina Integral Prof. Fernando Figueira (no.2.644.780).Besides, legal guardians of patients signed the informed assent form, and experts involved in the research signed the informed consent form.The study was conducted according to the stages shown in ►Figure 1.
In the authorization stage, permission to conduct the crosscultural adaptation was requested by e-mail and accepted by the author of the original article.For the direct translation, two independent and qualified Brazilian bilingual translators (one healthcare professional) translated the CHOP INTEND scale into Brazilian Portuguese.This process resulted in two de idade.As escalas disponíveis para avaliação das aquisições motoras mostram limitações para uso com crianças pequenas com doenças neuromusculares e fraqueza importante.Objetivo Realizar a tradução, adaptação transcultural e validação para a língua portuguesa do Brasil da Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND, na sigla em inglês).Métodos O presente estudo seguiu as etapas de tradução, síntese das traduções, retrotradução, consolidação por comitê de especialistas e teste com 13 pacientes com AME tipo 1. Foi avaliada a validade de conteúdo e a confiabilidade do instrumento.Resultados A escala foi traduzida considerando os aspectos semânticos, estruturais, idiomáticos e culturais.Todas as taxas de concordância foram > 0,8.O índice de validade de conteúdo geral do instrumento foi de 0,98.A confiabilidade interavaliadores analisada através do coeficiente de correlação intraclasse (ICC, na sigla em inglês) demonstrou um valor de ICC ¼ 0,998.Conclusão A versão da CHOP INTEND em português atende aos critérios de equivalência semântica e técnica em relação à versão original e apresenta validade de conteúdo e confiabilidade para seu uso na população de pacientes com AME tipo I.In the synthesis of the translation, a meeting was held with the translators and researchers to evaluate linguistic and contextual differences and obtain a single version in Brazilian Portuguese.Versions were compared, differences were identified, and adaptations were made until reaching a consensus on the synthesis of the translated versions (STV).
For the backtranslation stage, the STV was backtranslated into English by two independent English-speaking bilingual translators (one healthcare professional), resulting in two backtranslated versions (backtranslated version 1 [BTV1] and backtranslated version 2 [BTV2]).Afterward, researchers compared the two versions and discussed and adjusted possible semantic and conceptual differences that could compromise the meaning of words.Finally, the instrument was translated into Brazilian Portuguese to generate a prefinal version (PFV).
In the next stage, a face-to-face committee of 10 experts with practical experience in pediatric neurology (1 neurologist and 9 physical therapists) was formed; 6 had a Master's degree, and 2 had a PhD.
The original version, PTV1, PTV2, STV, BTV 1, BTV 2, and PFV were analyzed.The committee analyzed the equivalence between the translated and original instruments considering four aspects: semantic equivalence, which assessed grammatical and vocabulary issues and analyzed whether words had the same or more than one meaning; idiomatic equivalence, which observed whether the cultural meaning between languages was maintained in the translated items; experiential equivalence, which analyzed whether a given sentence or word was applicable in the target culture; and conceptual equivalence, which assessed whether a given term or expression had the same meaning across different cultures, even if properly translated. 22,23he committee also discussed whether terms were suitable for the pediatric population and could be applied to different regions of the country; they also added or replaced inappropriate, irrelevant, or ambiguous items with other suitable terms.Therefore, the committee helped elaborate the PFV used in the tests.
The content validity evaluated whether each item of the translated version of the CHOP INTEND was able to measure the motor function of patients with SMA type I.A 4-point Likert scale was applied with the following considerations: (1) the item is not relevant or not clear, (2) the item needs major revision to be relevant or clear, (3) the item is relevant or clear and needs minor revision, and (4) the item is relevant or clear.
The content validity index (CVI) used the following calculation to assess the agreement for each item between experts: CVI ¼ total number of responses 3 or 4 / total number of responses.A CVI > 0.7 was considered acceptable. 22,24n the pretest stage, the CHOP INTEND scale adapted to Brazilian Portuguese was applied to 13 patients with SMA type I treated at a referral rehabilitation service for neuromuscular diseases in the state of Pernambuco, Brazil.Inclusion criteria were patients aged from zero to 8 years old with a diagnosis of SMA 5q type I (genetic test), under noninvasive mechanical ventilation, and clinically stable during the assessment.We excluded those agitated or crying (or both); with confirmed cognitive, visual, or hearing deficits that hindered the test; or unable to maintain spontaneous breathing without noninvasive mechanical ventilation during the assessment.
The pretest assessed the quality, feasibility, and applicability of the translation and cross-cultural adaptation to ensure the understanding and clarity of the instrument and verify whether the time spent filling it was convenient.Initially, a single researcher assessed each patient using the translated version of the CHOP INTEND.The test was filmed and exhibited to three researchers who independently considered the highest score for each item on the scale.This strategy was used to avoid multiple assessments in a short period since patients with SMA type I are more vulnerable and less resistant to manipulation.The same precaution was used during the development of the original version of the CHOP INTEND scale. 13,14atistical analysis IBM Statistics for Windows version 20.0 (IBM Corp., Armonk, NY, USA) was used for data analysis.Descriptive statistics characterized the patients, and the intraclass correlation coefficient (ICC) 22,25 assessed the inter-rater agreement.Reliability was classified as unacceptable (< 0.70), acceptable (between 0.71 and 0.79), very good (between 0.80 and 0.89), or excellent (> 0.90). 26

RESULTS
The researchers synthesized the translation based on PTV1 and PTV2.Acronyms and abbreviations were replaced with full terms to adequate the terms according to clinical and patient identification data.The term Gtube was replaced by gastrostomia, BiPAP by ventilação não-invasiva, upper respiratory infection (URI) by infecção respiratória, medical register (MR) by registro, date of evaluation (DOE) by data de avaliação, date of birth (DOB) by data de nascimento, and hours (HRS) by horas.
The researchers also discussed the best term to apply in the case of word divergence between the translators.The consensus applied by researchers for developing the STV is shown in ►Table 1.
At the backtranslation stage, the native English-speaking translators presented their version of the scale translated back into English.Minimal discrepancies between the versions revealed synonyms that did not change the understanding of the expressions, were close to the original version, and were considered appropriate after evaluation by the author of the original scale.
The committee of experts analyzed all previous versions and decided to include the term duração da avaliação in the header; replace the term bed surface with superfície; replace the term hand grip with preensão palmar (item 3); replace the phrase allow the infant to derotate (item 7) with permita que a criança tente rolar; adjust the term able to get arm of body to retirar o braço de próximo do corpo (item 8); add the term gentilmente to the verb beliscar (items 10 and 11); replace head hangs with cabeça fica pendente (item 12); replace head/neck extension with extensão da cabeça/cervical (item 15); and replace spinal incurvation with flexão lateral da coluna in item 16.The content of each item of the scale in PTV1 and PTV2 was validated by the committee of experts (►Table 2).All agreement rates were > 0.8, and the overall CVI of the instrument was 0.98, calculated as the mean value of the item divided by the number of items.
In the pretest of the final Brazilian version of the CHOP INTEND, the scale was applied to a convenience sample of 13 patients (►Table 3).Five out of 18 patients with SMA type I registered at the service were excluded from the study: 3 could not complete the test under spontaneous breathing, while the behavior of 2 patients was not favorable to the assessment.Patients were predominantly male (76.92%) and had a mean age of 17.23 AE 20.24 months old; the mean assessment time was 47.3 minutes.
In the reliability analysis, the scores assigned by the three researchers for each item on the scale are shown in ►Table 4. The inter-rater reliability was considered excellent (ICC ¼ 0.998).

DISCUSSION
The translation allowed adjustments and substitutions of the terms to guarantee equivalence based on the consensus of researchers, translators, and experts.Content validity showed    Brazilian Version of the Chop Intend Scale Alves et al.
agreement rates > 0.8, the overall CVI of the instrument was 0.98, and the final Brazilian Portuguese version presented good inter-rater reliability (ICC ¼ 0.998).
The current scenario of proactive care and therapeutic innovations indicates a change in the phenotypes of patients with SMA type I. 27,28 Therefore, the use of standardized measures for assessment is crucial to integrate clinical practice with research. 29,30Besides, the scales currently available in Brazil to assess infant development require different postures, are not sensitive, specific, or responsive to changes, and may produce a floor effect in patients with SMA type I. 10,15 The CHOP INTEND is a valid instrument used worldwide, which makes its translation into Brazilian Portuguese more convenient than creating a new instrument. 10,15The recommended requirements were followed to enable a proper and accurate Brazilian version of the CHOP INTEND and guarantee the quality of results. 20e did not find publications on CHOP INTEND translation and cross-cultural adaptation protocols for other languages/ countries.An international multicenter study, about a training protocol for evaluators of clinical trials in countries of Europe, Asia, and the Pacific region, reported that the test materials applied to patients with SMA, including the CHOP INTEND, were only translated into the local language based on the needs of the evaluators. 16n our translation methodology, according to a formal protocol, the difficulties encountered (for example, idiomatic expressions, cultural variations, and regionalisms) were resolved by consensus between translators, researchers, and experts, who addressed the most appropriate terms in Brazilian Portuguese.We also carefully maintained the aesthetic aspect of the instrument and kept it close to the original document.
Although the convenience sample of 13 patients was small, we considered it adequate for this type of methodological study because SMA is a rare disease with possible respiratory complications, such as recurrent infections requiring invasive mechanical ventilation, and short life expectancy. 31,32n the development study of CHOP INTEND, the intrarater reliability analysis included only 9 patients and the interrater reliability test, considering its possible application in other rare neuromuscular conditions in childhood, involved 10 children with other diseases. 13n further evaluation for concurrent validation of the scale, 27 patients with SMA from 3 to 260 months old (81% of them < 5 years old) were included through a multicenter study, which correlated CHOP INTEND scores with the time of NIV use.It was shown that patients who were older and required longer ventilation time presented lower scores on the scale. 14As in this study, our sample was also composed of subjects who did not require invasive ventilation.
Therefore, we believe the Brazilian version of the CHOP INTEND met semantic and technical equivalence criteria with the original version and presented excellent content validity and reliability to support its use in Brazilian patients with SMA type I. (►Supplementary Material -https://www.arquivosdeneuropsiquiatria.org/wp-content/uploads/2023/09/ANP-2022.0302-Supplementary-Material.zip).

Figure 1
Figure 1 Stages of the transcultural adaptation of the CHOP INTEND to Brazilian Portuguese.Abbreviations: OV, original version; PTV1 and PTV2, Portuguese translated version; STV, synthesis of the translated versions; BTV1 and BTV2, backtranslation to English; PFV, prefinal version; TV, test version; FV, final version.
Abbreviations: NPT, Not Possible to Test.

Table 1
Stage 1 of the cross-cultural adaptation process Brazilian Version of the Chop Intend Scale Alves et al. 819 Arquivos de Neuro-Psiquiatria Vol.81 No. 9/2023 © 2023.The Author(s).

Table 2
Content validity indexcommittee of experts

Table 4
Test of the final Brazilian Portuguese version of the CHOP INTEND scale.Score of the three researchers (A, B, and C) per item for each patient P a t i e n t